The present invention relates to an insert molding method of a receptacle connector.
There is a receptacle connector (a female type connector) having a terminal 21 formed in a tulip shape in a side elevational view in which a curved portion 21a curving in a thickness direction thereof is formed, as shown in FIG. 6(a), for the purpose of gripping a plug connector (a male type connector) connected thereto.
In the case of forming the receptacle connector provided with the terminal in which the curved portion is formed in accordance with an insert molding method, it is necessary to form a metal mold with keeping clear of the curved portion of the terminal.
In the case of a connector having one row of terminal group in which a plurality of terminals are provided in parallel in a width direction, it is possible to easily execute the insert molding by forming a pair of metal molds 22 so as to run off the curved portion 21a, as shown in FIG. 6(a).
Further, as disclosed in Japanese Patent Publication No. 8-415 filed by the inventor of the present application, even in the case that the terminal group is constituted by two rows of connectors, the insert molding can be executed. In particular, as shown in FIG. 6(b), the insert molding is executed by forming a metal mold core 23 placed in a side of the curved portion 21a so as to run off the curves portion 21a in the terminal group, bringing the metal mold members 22 to which the terminal group 21 is attached into contact from both sides of the core 23 so as to form a cavity 24, and injecting a resin within the cavity 24 so as to form a mold portion 25.
Thereafter, as shown in FIG. 6(c), the insert molding of the receptacle connector in which the terminal group is constituted by two rows of terminals is excuted, by drawing out the connector from the core 23 within an elastic limit of the curved portion 21a in the terminal group 21.
On the contrary, in recent years, a connector provided with a lot of terminal groups is required, and a connector provided with three or more rows of terminal groups is also desired. However, in the case that the terminal groups having the curved portions are provided in three rows or more, there are generated two or more portions in which the curved portions are overlapped and an interval thereof is made narrow, so that it is impossible to form in accordance with the conventional insert molding method.
Accordingly, in conventional, in the case of forming the receptacle connector provided with three or more rows of terminal groups, the formation is executed by insert molding one row of terminal group so as to form a mold portion, and thereafter combining them in three rows or more rows so as to adhere in accordance with an adhesive agent or an ultrasonic welding, or pressure inserting the mold portion combined in three or more rows into an independently formed case.
However, in the connector formed in accordance with the method mentioned above, there is a case that distances between the terminal groups are dispersed in some adhering states between the respective mold portions. Since a transmission impedance of the connector is dispersed when the distances between the terminal groups are dispersed, there is a risk that a transmission loss of a signal is increased particularly in the case of the connector for transmitting the signal having a high frequency.
Further, in accordance with the method mentioned above, since it is necessary to once execute the insert molding and thereafter combine the connector in three or more rows so as to fix, there is a disadvantage that a manufacturing step becomes complex.
An object of the present invention is to improve an insert molding method of a receptacle connector, and more particularly to provide an insert molding method of a receptacle connector which can keep a distance between terminals constant and can easily manufacture, even in the receptacle connector having three or more rows of terminal groups, for the purpose of solving the disadvantage mentioned above.
In order to achieve the object mentioned above, the present invention is an insert molding method of a receptacle connector having a terminal group in which a plurality of terminals having tulip-shaped curved portions in a side view are provided in a width direction in a front end of a flat plate portion, and a mold portion which is provided with at least three rows of the terminal groups in a thickness direction in parallel and is integrally formed with a part of the flat plate portion, characterized by the following matters.
At first, a cavity for forming the mold portion is structured such as to be formed by being surrounded by a pair of metal mold bodies formed so as to move close to and apart from each other in a thickness direction of the terminal groups, having first receiving potions for receiving the curved portion and forming a side surface of the cavity, a plurality of front cores arranged between the terminal groups, having second receiving portions formed so that the curved portion can deflect in the thickness direction, formed so as to freely move close to a front portion of the terminal and apart therefrom and forming a front surface of the cavity, and a plurality of rear cores arranged between the terminal groups at the back of the front cores and forming a rear surface of the cavity. Further, the receptacle connector is formed in accordance with the following steps.
At first, there is provided a step of receiving the curved portions in the first receiving portion so as to hold the terminals arranged at both ends, among the terminal groups arranged in three rows or more in parallel, in the pair of metal mold body, and respectively gripping flat plate portions of the terminal groups arranged at middle positions by a plurality of rear cores.
Next, there is provided a step of moving forward the front cores arranged in one side in the thickness direction of the curved portion from front portions of the curved portions so as to deflect the curved portions of the terminal groups, receiving the curved portions in the second receiving portion, thereafter moving forward the front cores arranged in another side in the thickness direction of the curved portion from front portions of the curved portions so as to deflect the curved portions of the terminal groups, and receiving the curved portions in the second receiving portion.
There are provided a step of thereafter moving a pair of metal mold bodies close to each other so as to form the cavity, a step of injecting a resin within the cavity so as to cure the resin, thereby forming the mold portion, and a step of moving a pair of metal mold bodies apart from each other.
Next, there is provided a step of moving backward the front cores arranged in one side in the thickness direction of the curved portion so as to remove while deflecting the curved portions and thereafter moving backward the front cores arranged in another side so as to remove while deflecting the curved portion.
Further, there is provided a step of removing the terminal group and the mold portion from the rear cores.
In accordance with the insert molding method of the receptacle connector of the present invention, among the terminal groups arranged in three or more rows in parallel, the terminal groups arranged at the middle position are gripped by the rear cores, and the front cores are moved forward one side by one side toward the gripped terminal groups with respect to the terminal groups.
When moving forward the front cores in one side toward the terminal groups, the curved portion is pressed to the front cores from one direction, so that the terminal groups are deflected.
Further, when moving forward the front cores in one side, the curved portions are received in the second receiving portion provided in the front cores. Next, when moving forward the front cores in another side toward the terminal groups, the curved portions are pressed to the front cores from another side.
At this time, since the curved portions are received in the second receiving portion of the front cores in one side, the curved portions of the terminal elements are deflected within the second receiving portion.
When further moving forward the front cores in another side, the curved portions are received in the second receiving portions provided in the front cores.
Next, by moving a pair of metal mold main bodies close to the front cores and the rear cores together with the terminal groups arranged at both end positions, the cavity is formed.
At this time, the curved portions of the terminal groups arranged at both end positions are received in the first receiving portion.
As mentioned above, in accordance with the present invention, even in the case that the respective curved portions are overlapped between the terminal groups in three rows or more and the number of the portions having the narrow interval is two or more, it is possible to arrange the front cores between the terminal groups so as to form the cavity.
Accordingly, even in the case of the receptacle connector provided with three rows or more terminal groups, it can be formed in accordance with the insert molding, so that it is possible to keep the distance between the terminal groups constant.
Therefore, it is possible to form the connector in which the transmission impedance is not dispersed and there is no fear that the transmission loss is not increased even in the case of transmitting the signal having the high frequency.
Further, since it is possible to form the receptacle connector provided with three or more rows of terminal groups in accordance with one insert molding operation, it is easy to manufacture the receptacle connector mentioned above.
Further, in the insert molding method of the receptacle connector in accordance with the present invention, it is preferable to sequentially move forward the front cores toward the curved portion so as to move from the front cores arranged in an end portion in one side toward an end portion in another side, among the front cores, in the step of moving forward the cores from the front portion of the curved portion, and to sequentially move backward the front cores so as to move from the front cores arranged in the end portion in one side toward the end portion in another side, among the front cores, in the step of moving backward the front cores so as to remove, thereby removing the front cores.
As mentioned above, by sequentially moving forward and backward the front cores from the end portion in one side, it is possible to sequentially move forward and backward the front cores from one side of the curved portion.
Further, even in the case of increasing or reducing the number of the rows of the terminal groups provided in parallel, since it is sufficient to sequentially move forward and backward the front cores from one side, it is possible to correspond to the increase and reduction of the number of the rows of the terminal groups without changing the control of moving forward and backward the front cores.